Industrial WLAN System with Accurate Time Synchronization on Software Defined Radio

This paper presents a hardware implementation of low latency and highly accurate time synchronization for Industrial WLAN systems. The design of our media access control (MAC) layer supports both asynchronous and synchronous multi-user transmission protocols. Low overhead Packet Division Multiple Access (PDMA) scheme is utilized for Multi-user Downlink transmission, while Frequency Division Multiple Access (FDMA) is employed for the uplink transmission. The design of the physical (PHY) layer system is developed based on fast and deterministic communication. The proposed industrial WLAN system is developed on Software Defined Radio (SDR). The experimental results show that the wireless control communication can be achieved to control motors with a high accuracy Precision Time Protocol (PTP) in nano-second level from 200 ns to 300 ns which is less than 1 ms compared to PROFINET wireless standard.